JPH02123310A - Auto focus mechanism of microscope - Google Patents

Abstract

PURPOSE:To execute the auto focus at a high speed and with high accuracy by constituting the title mechanism of an infinity correcting optical system for converting an image of an observation object to a light beam being parallel to an optical axis by an objective lens, and thereafter, forming an image by an image forming lens. CONSTITUTION:An image of an observation object 8 becomes a light beam being parallel to an optical axis by an objective lens 3, and thereafter, formed to an intermediate image by an image forming lens 2, and observed through an eyepiece 1. In an optical system constituted in such a way, the condition for adjusting the focus in accordance with height of the observation object 8 is only a fact that a distance between the objective lens 3 and the observation object 8 is made equal to the front side focal distance of the objective lens 3, and a distance between the image forming lens 2 and the objective lens 3 does not exert the influence on the focus and the overall magnification of a microscope. Accordingly, since the focus is adjusted automatically, the part driven by a motor 6 can be made small in size and light in weight. In such a way, the auto focus can be executed at a high speed and with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an autofocus mechanism that automatically focuses a microscope.

[Prior Art] The autofocus mechanism of a conventional microscope uses a motor to move the entire lens barrel to a focused position, as shown in FIG.

[Problems to be Solved by the Invention] However, with the conventional technology, it was difficult to achieve high-speed and high-precision focusing due to the large weight of the movable parts.The present invention therefore aims to solve the above-mentioned problems. The purpose of this is to provide a single-microscope autofocus mechanism that is capable of high-speed, high-precision focusing.

[Means for Solving the Problems] In order to solve the above problems, the autofocus mechanism of the microscope 2 of the present invention converts the image of the observed object into a beam parallel to the optical axis using an objective lens, and then converts the image into a beam parallel to the optical axis using an imaging lens. The present invention is characterized in that an infinity correcting optical system is configured to form an image at a distance, and focusing is automatically performed by driving only the objective lens by a motor.

[Function] In the optical system configured as above, the total magnification of the microscope does not change even if the distance between the objective lens and the imaging lens changes, so in order to focus, only the objective lens must be used. All you have to do is move the object to be observed at the front focus position. Therefore, in order to automatically focus, the part driven by the motor can be made smaller and lighter, allowing for high-speed, high-precision autofocus. It becomes possible [
Embodiment] FIG. 1 is a schematic diagram showing an embodiment of the present invention.

After the image of the observation object 8 is converted into a beam of light parallel to the optical axis by the objective lens 3, an intermediate image is formed by the imaging lens 2 and observed through the eyepiece lens 1. In the optical system configured in this way, the only condition for adjusting the focus according to the height of the object 8 to be observed is that the distance between the objective lens 3 and the object 8 to be observed is equal to the front focal length of the objective lens 6. The distance between the imaging lens 2 and the objective lens 3 does not affect the focus or the overall magnification of the microscope. Therefore, observation object 8
In order to focus, the lens barrel 4 in which the eyepiece lens 1 and the imaging lens 2 are incorporated remains fixed to the support 5, and only the objective lens 5 incorporated in the slider 7 is driven up and down by the motor 6. , the observation object 8 is positioned at the front focal position of the objective lens 3.

FIG. 6 is a schematic diagram showing another embodiment of the present invention. By incorporating an actuator 9 that drives the objective lens 3 up and down into the lens barrel 4, the drive unit can be made smaller and lighter, thereby achieving highly responsive autofocus. Here, the actuator 9 can be selected from a voice coil motor, an ultrasonic motor, a piezoelectric ceramic, etc. depending on its intended use.

[Effects of the Invention/K] The present invention uses an infinity correcting optical system to form an image of an object to be observed into a beam of light parallel to the optical axis using an objective lens, and then to form an image using an imaging lens. By making the drive unit smaller and lighter with only the objective lens, high speed and
This has the effect of realizing highly accurate autofocus.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, FIG. 2 is a schematic diagram showing a conventional autofocus mechanism, and FIG.
The figure is a schematic diagram showing another embodiment of the invention. 1...Eyepiece 2...Imaging lens 5...Objective lens 4...Mirror tube 5・・・・・・・・・Support 6・・・・・・Motor 7゛°°°°°°゛°Slider 8・・・・・・Object to be observed 9・・・・...Applicant for actuators and above Seiko Epson Co., Ltd. Agent Patent attorney Kizobe Suzuki (and 1 other person) 3rd Division

Claims (1)

[Claims] An infinity correction optical system is constructed in which an object to be observed is converted into a beam of light parallel to the optical axis using an objective lens, and then the image is formed by an imaging lens, and only the objective lens is driven by a motor to automatically perform focusing. A microscope autofocus mechanism featuring: